1) Nothing down the left side of the start menu stays open. If I click on the power button it flashes the options and closes. User flashes options and closes.
2) Action center on the complete other side of the task bar flashes the notifications and closes right away.
3) Wireless network selector same thing. Displays available wireless networks and closes right away.
4) Cortana search window flickers and I have to press a key two or three times until it finally shows up in the search window.
I have 20-30 computers doing this. All of them started after the upgrade to 1703. New profile doesn't do anything different. Repair install (reset) doesn't do anything different. These are different computer at different customers. Desktops and Laptops. About the only thing they have in common is that they were all upgraded from WIndows 7. The original 1511 worked fine. Upgrade to 1603? worked fine. Everything fell apart with the upgrade to 1703.